About DMA mem and IO Server

[Yuxin Ren]

Thank you very much for your reply.
But I still have some questions.
Can I alloc and free memory without dataspace?

I know we can do memory mapping over IPC, using L4::Ipc::Snd_fpage
and L4::Ipc::Rcv_fpage.
So after a client gets a piece of memory mapping in, how does it ummap that
memory? Still use deattach or anyting else?

Does Fiasco manage memory in user level or kernel level? That is to say,
attach and deattach function are just system call or normal
IPC invoking some serve in the user level?

Thank you


On Mon, May 12, 2014 at 5:51 AM, Martin Schröder <
martin.schroeder at openlimit.com> wrote:

> Am 12.05.2014 09:34, schrieb Taeung:
>
>  Thanks Martin :-)
>>
>> Referencing website link which you give me , I'm trying to secure
>> Ethernet on L4Linux.
>> I've got eth0 and configure ip address, netmask , etc.
>> But if I do 'ping 8.8.8.8' for test, error occur such as 'Error
>> connecting: Network is unreachable'.
>>
>
> Which version of fec_main.c are you using? The one from l4re-snapshot-
> 2014022818.tar.xz or another?
>
>
>  I suspect that the problem is about DMA mem.
>>
>
> Maybe, the buffers and the descriptors reside in the DMA mem, so if you
> can configure FEC but no payload goes thgrough, this could indicate a
> problem.
>
>
>  As below , there is 'WARNING: phys mmio resource allocation failed' log
>> message..
>> What is the problem ?
>>
>
> I don't know the reason. But I also get the same WARNING (also twice) for
> each DMAMEM on my board - of course the beginning-end addresses differ.
>
>  May this problem be the reason why network is unreachable  ?
>>
>> ========================
>> ..(omitted)..
>>
>> IO      | Io service
>> IO      | Verboseness level: 4
>> IO      | unused physical memory space:
>> IO      |   [00000001000000-0000000fffffff]
>> IO      |   [00000050000000-000000ffffffff]
>> IO      | Loading: config 'rom/imx6q.io'
>> *IO      | WARNING: phys mmio resource allocation failed**
>> **IO      | <0x1bf18>IOMEM [00000010426000-000000104a5fff 80000]
>> non-pref (32bit) (align=7ffff flags=c002)**
>> **IO      | WARNING: phys mmio resource allocation failed**
>> **IO      | <0x1bf18>IOMEM [00000010426000-000000104a5fff 80000]
>> non-pref (32bit) (align=7ffff flags=c002)*
>>
>> IO      | P6Device: l4linux ""
>> IO      |   P6Device: (noname) "L40009"
>> IO      |   P6Device: imx6q-fec.dev0 "imx6q-fec.0"
>> IO      | <0x14678>    IOMEM   [00000002188000-0000000218bfff 4000]
>> non-pref (32bit) (align=3fff flags=4002)
>> IO      | <0x1be28>    IRQ     [00000000000096-00000000000096 1] none
>> (32bit) (align=0 flags=4001)
>> IO      |   P6Device: dmamem "dmamem"
>> IO      | <0x1bf18>    IOMEM   [00000010426000-000000104a5fff 80000]
>> non-pref (32bit) (align=7ffff flags=c002)
>>
>> ..(omitted)..
>> ========================
>>
>> I'd appreciate whoever give me hints.
>>
>
> Did you try to use a 10/100 MBit/s port instead of Gigabit Ethernet? The
> right PHY_INTERFACE_MODE MII / RMII / RGMII is also set according to your
> board (kernel/arch-arm/mach_setup.c)
>
> I would suggest to add some kprintf code in fec_main.c and dump the
> received/sent ethernet buffers. Beginning with fec_enet_bd_init,
> fec_enet_interrupt and fec_enet_tx/_rc to see if the buffers are valid.
>
>
>  - Taeung -
>>
>>
>>
>
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